Effect of Conical Profile on the Transmission of Elastic Waves From Cylindrical Waveguide to Bulk

Abstract This paper studies the transmission of elastic waves into test specimens for cylindrical waveguide-based ultrasonic transducers. However, to achieve better mode focusing, topographical waveguides with conical profiles were studied. Finite element simulations were used to study wave propagation and transmission into specimen samples using such “transmission horns.” Fundamental longitudinal mode L(0,1) was generated in cylindrical rods. Results from both finite element simulations and experiments show that a 50-deg conical transition profile help achieve better transmission and beam directionality into the specimen and also better reception of the back wall reflections at the waveguide as compared to a simple cylindrical rod waveguide.

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Studies on the effect of inclination of reinforcement and wave propagation in concrete cores through finite element simulations

Materials Today Proceedings ◽

10.1016/j.matpr.2020.11.456 ◽

2021 ◽

Author(s):

S. Herald Lessly ◽

R. Senthil ◽

U. Ellampooranan

Keyword(s):

Finite Element ◽

Wave Propagation ◽

Finite Element Simulations

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Nondestructive evaluation of defects in concrete structures based on finite element simulations of ultrasonic wave propagation

Nondestructive Testing And Evaluation ◽

10.1080/10589751003658057 ◽

2010 ◽

Vol 25 (4) ◽

pp. 289-315 ◽

Cited By ~ 13

Author(s):

Giuseppe Acciani ◽

Girolamo Fornarelli ◽

Antonio Giaquinto ◽

Domenico Maiullari

Keyword(s):

Finite Element ◽

Wave Propagation ◽

Nondestructive Evaluation ◽

Ultrasonic Wave ◽

Concrete Structures ◽

Finite Element Simulations ◽

Ultrasonic Wave Propagation

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Modeling and Analysis of Nonlinear Wave Propagation in One-Dimensional Phononic Structures

Journal of Vibration and Acoustics ◽

10.1115/1.4039570 ◽

2018 ◽

Vol 140 (6) ◽

Cited By ~ 3

Author(s):

M. Liu ◽

W. D. Zhu

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Wave Propagation ◽

Band Structure ◽

Band Gap ◽

Nonlinear Wave ◽

Elastic Waves ◽

Propagation Characteristics ◽

Nonlinear Wave Propagation ◽

Weakly Nonlinear

Different from elastic waves in linear periodic structures, those in phononic crystals (PCs) with nonlinear properties can exhibit more interesting phenomena. Linear dispersion relations cannot accurately predict band-gap variations under finite-amplitude wave motions; creating nonlinear PCs remains challenging and few examples have been studied. Recent studies in the literature mainly focus on discrete chain-like systems; most studies only consider weakly nonlinear regimes and cannot accurately obtain some relations between wave propagation characteristics and general nonlinearities. This paper presents propagation characteristics of longitudinal elastic waves in a thin rod and coupled longitudinal and transverse waves in an Euler–Bernoulli beam using their exact Green–Lagrange strain relations. We derive band structure relations for a periodic rod and beam and predict their nonlinear wave propagation characteristics using the B-spline wavelet on the interval (BSWI) finite element method. Influences of nonlinearities on wave propagation characteristics are discussed. Numerical examples show that the proposed method is more effective for nonlinear static and band structure problems than the traditional finite element method and illustrate that nonlinearities can cause band-gap width and location changes, which is similar to results reported in the literature for discrete systems. The proposed methodology is not restricted to weakly nonlinear systems and can be used to accurately predict wave propagation characteristics of nonlinear structures. This study can provide good support for engineering applications, such as sound and vibration control using tunable band gaps of nonlinear PCs.

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